Oil & Fuel Off Road vs Highway Diesel

[Ken Cunningham]

Hi all,
Went to the gas station today for my first load of desiel. I thought the only difference between the two was the taxes. I noticed the pump said high sulphur for the off road desiel, so I went ahead and got the highway type. Does the sulfur content do any thing, other than maybe the way it smells? The price difference was 30 something cents a gallon. Which one do you use in yours?

 

[Ductape]

Either works in your tractor. You can't run the high sulfer stuff in the new on road dieselvehicles with the particulate filters in the exhaust.

 

[ScottK]

In Washington state they appear to be the same except they add pink dye to the off-road and don't charge fuel tax (saves 0.70 per gallon here). How much difference in price out there?

 

[exiled]

Ken, all that they are making now is ultr-low.

Sulfer plays a big part in diesel. It is the fuel lube. By taking it out the manufactures has to put something back in. The goverment's standard is very low to several engine manufactures. If your tractor is older than an 07 model than the high sulfer is the way to go. The only difference between off road and highway is color. Off road is dyed cause of tax reasons. Here in Al a think ours is around 63 cents a gal.

 

[Skyco]

Sulpher is not a lube in diesel. The process of removing the sulpher removes the desireable lubricant properties as well. IOW you can't add sulphur back to diesel to improve its lube properties.

 

[exiled]

Sulpher is not a lube in diesel. The process of removing the sulpher removes the desireable lubricant properties as well. IOW you can't add sulphur back to diesel to improve its lube properties.

I'm not going to argue what sulfur is or aint. Back to the point of what I was saying if you have an older than 07 model your engine will do better with the low -regular sulfur levels than the ultra-low. Ultra-low by it's self cant pass the scar test. The goverment is'nt putting strect enough standards on the manufactors on how much lube to put back once they removed the lubricant from the fuel. Low sulfur is suppose to damage 07 and newer engines. I know for a fact an 07 Ford 6.0L built in mid 07 will run on low. A friend of mine Has an 07 F350 and he buys 7000 gals of fuel at a time. Of course its delivered to his farm in 3500 gal at a time. He bought his truck and had alot of low left. He did'nt even know about the risk untell much later. He is still running low. I have'nt see the fuel truck at his tanks refilling.
I dont know why low is suppose to hurt 07 and later. Maybe Ford Did'nt switch everything over untell ultra finally got everywhere. I dont know. Everybody else's Diesels might not be so lucky.

 

[sd624]

Running low sulfur or regular diesel in a 07 and later Ford 6.4l wont hurt the engine but what it will do is plug the DPF. The DPF is a particulate trap that periodically has to have the accumulated soot burned off. To do this fuel is injected on the exhaust stroke which pumps raw fuel into the exhaust diesel oxidation catalyst. This raises the front of the DPF to around 1100F which burns the soot away. When the truck is in regen you get about 6 to 9 MPG. The higher the sulfur the more regens which cost you lots of MPG's and $$$$.

This is coming soon to a tractor near you. John Deere is experimenting right now with the same DPF setup that Ford uses.

John Deere allows the use of 15 ppm Ultra-Low-Sulfur diesel fuel (more commonly known as ULSD or S15 Diesel Fuels) in all Engine Models as long as the diesel fuel used meets the latest ASTM D-975 diesel fuel lubricity specification which allows up to a 520-micron maximum wear scar diameter measured on a High Frequency Reciprocating Test Rig (HFRR). This new ASTM lubricity standard was introduced on 01 January 2005, and applies to both on-road and off-road diesel fuels.

Additives for lubricity should not be necessary. Like Low Sulfur Diesel fuel, ULSD fuel requires good lubricity and corrosion inhibitors to prevent unacceptable engine wear. Additives to increase lubricity and to inhibit corrosion will be added to ULSD fuel prior to its retail sale. With these additives, ULSD fuel is expected to perform as well as Low Sulfur Diesel fuel.

Generally speaking, the same oil refinery process used to reduce Sulfur content also removes Oxygen, Nitrogen, aromatic compounds, and other key characteristics in diesel fuel, which are considered to be natural fuel lubricity agents. Sulfur content by itself has little to do with fuel lubricity. Many oil refineries are now adding back in other fuel lubricity agents to prevent the former diesel fuel lubricity and rubber seal deterioration fiasco experienced back in 1993 and 1994. Reducing the sulfur content of diesel fuel from 500 ppm to 15 ppm will have no significant effect on engine fuel economy, fuel density, fuel heating value, or fuel lubricity.

Sorry for the long post!

SD

 

[dirtworksequip]

OH NO.................here we go again! Come December 1st, 2014 all we will have is Ultra-low sulfur.

Sincerely, Dirt

 

[Ken Cunningham]

So off road is better for the engine?

 

[Heywood Jannockitov]

I would think that the lower the sulfur level in the fuel, the better. During the combustion process sulfur dioxide is produced. Mix sulfur dioxide with water, in the form of condensation and what do you get? Sulfuric acid, which corrodes metal. Why adhering to specified oil change intervals in diesels is crucial.